A typical electronic surveillance device consists of two main components. The first component is a microphone or transducer which picks up the sounds present in a given space, such as a room, and converts them into an electronic signal. This electronic signal is then transferred to a transmitter which converts the electronic signal into an electromagnetic signal which is then transmitted. The transmitted electromagnetic signal may be radio, microwave, light, low frequency electrical or other, and it may be transmitted in a number of ways such as through space or over existing wires. It is the presence of this transmitted electromagnetic signal that makes an electronic surveillance device subject to detection.
Some detection devices require the introduction of specialized sound into the environment which is to be searched for an electronic surveillance device. However, the introduction of such specialized sounds would indicate that the bug was either suspected or had been detected thus enabling the person using the electronic surveillance device to turn it off, if possible, or abandon it.
The current state of the art relies upon an operator listening to the sounds present in a room and to signals intercepted by a receiver. A bug has been detected when the received signal (as played through speakers or a head set) matches the sounds within a room. However, if there is noise present in the room it becomes difficult if not impossible for an operator to detect any correlation.
It has been a limitation of prior art devices to be to some extent frequency dependent; that is, the absence of a particular frequency, or the presence of too many frequencies (such as noise) degrades their ability to detect bugs present in a room.
The present device overcomes such limitations by being frequency independent and will function effectively in an environment containing one frequency, multiple frequencies, changing frequencies or just noise.